If the temperature changes in a chemical reaction, what has occured?

A) energy was destroyed

B) energy was created

C) there was no energy transfer

D) energy was transferred

Spirometry measures the air taken in by and expelled from the lungs. True or False?

Identify the double displacement reactions among the following: 1. KCl (aq) + AgNO3 (aq) - AgCl (s) + KNO3 (aq) 2. Na2SO4 (aq) + BaCl2 (aq) →BaSO4 (s) + 2NaCl (aq) 3.

Which of the following best explains the law of superposition? A) In rock layers, the oldest layers are at the bottom and the youngest are at the top B) In rock layers, the youngest layers are at the bottom and the oldest are at the top C) Due to

Name two gases which are supplied in compressed form in homes and hospitals?

Products and reactants are used and created at the same rate when a reaction is at this stage A. Le Chateliers principle B. Catalyst C. Balanced Equation D. Chemical equilibrium

Making observations is the first step in the scientific method. Why don't scientists stop with the first step when creating an experiment? A.

Brass is an example of

A molecule has four bonded atoms around a central atom. The central atom does not have any lone pairs of electrons. What is the geometry of the molecule? Bent Linear Trigonal planar Tetrahedral

Using the periodic tables, identify the heaviest member of each of the following groups: (a) alkali metals (b) chalcogens (c) noble gases (d) alkaline earth metals

Select the best answer for the question. 13. Which statement accurately describes the relationship between mass and weight? A. An object with twice the mass of another object will weigh twice as much B.